Combines are large self-propelled vehicles used for harvesting and threshing agricultural crop in the field. A harvesting head is typically disposed across the front of the combine vehicle supported on a feederhouse. This harvesting head is configured to cut and convey the crop into the combine vehicle itself where it is threshed, separated, and cleaned.
Traditional harvesting heads included an elongate rigid frame to which harvesting implements are added such as row units, reciprocating knife assemblies, augers, reels, and endless belt conveyors. One such type of harvesting head is called a “draper platform” or “draper”.
Draper platforms have an elongate frame on which are mounted left and right side endless belt conveyors mounted immediately behind a reciprocating knife. These endless conveyors convey cut crop material inward to a center portion of the draper platform, depositing them on a center conveyor that moves rearward. The center conveyor carries the material to and through an aperture at the rear of the draper platform frame, where it is deposited in an elevating conveyor called a feederhouse, which carries the cut crop material into the combine vehicle for threshing, separating and cleaning. Above the mentioned aperture at the rear of the draper platform frame, a rotationally driven, upper cylindrical conveyor drum with frusto-conical end sections and protruding fingers is usually provided for assisting the crop flow by undershot feeding.
The crop coming from the left and right endless belt conveyors thus needs to change its direction in the center of the platform from a lateral direction into a rearward direction. Under unfavorable circumstances, this area can be due to lack of moving feed elements between the rear end of the center conveyor and the upper conveyor drum subject to crop stalling, which allows crop to leak from the platform, causing crop losses and/or material to lodge in the left and right endless belts with the result of belt stalling. Both issues result in lost time and lost profits for the customer.
This problem is addressed by the arrangement described in the independent claim. Further advantages are provided by the dependent claims.